一、Java 循环删除list中指定元素

增强for循环删除指定元素

@Test

public void test(){

String[] strs={"a", "b", "c", "f", "b", "e", "d"};

Listlist = new ArrayList<>(Arrays.asList(strs));

for (String s : list) {

System.out.println("------" + s + "------");

if ("b".equals(s)) {

list.remove(s);

}

}

}

结果：

java.util.ConcurrentModificationException

异常

iterator删除指定元素

@Test

public void test(){

String[] strs={"a", "b", "c", "f", "b", "e", "d"};

Listlist = new ArrayList<>(Arrays.asList(strs));

Iteratoriterator = list.iterator();

while (iterator.hasNext()) {

String next = iterator.next();

System.out.println("------"+next+"------");

if ("b".equals(next)) {

iterator.remove();

}

}

System.out.println(list.toString());

}

CopyOnWriteArrayList

@Test

public void test(){

Listlist = new ArrayList<>();

list.add("aa");

list.add("bb");

list.add("cc");

CopyOnWriteArrayListcowList = new CopyOnWriteArrayList<>(list);

for (String str : cowList) {

if ("aa".equals(str)) {

cowList.remove(str);

}

}

System.out.println(cowList.size());

}

普通for循环

for (int i = 0; i < list.size(); i++) {

if ("2".equals(list.get(i))) {

list.remove(i);

}

}

有重复元素的删除方法

Listlist = new ArrayList<>();

list.add("a");

list.add("a");

list.add("c");

list.add("d");

list.add("a");

int i=0,size= list.size();

for (; i < size; i++) {

if ("a".equals(list.get(i))) {

list.remove(i);

i-=1;

size-=1;

}

}

for (String str : list) {

log.info(str);

}